Publication Date:
2020-11-05
Description:
Background and Aims. Prediction of treatment efficacy is an active and growing field of pharmacology. In the Fondazione Italiana Linfomi (FIL) MCL0208 phase III trial (NCT02354313), a 24 months lenalidomide maintenance (LM, 15 mg days 1-21 every 28 days) after high-dose immuno-chemotherapy followed by autologous transplantation (ASCT) in 300 frontline mantle cell lymphoma (MCL) patients showed substantial clinical activity in terms of Progression-Free Survival (PFS) vs observation (OBS). However, this benefit seemed not uniform across patient series. To deeper investigate the differential pattern of response to lenalidomide, a wide analysis of the host pharmacogenomics (PG) background was planned, in order to dissect whether specific germline polymorphisms of transmembrane transporters, metabolic enzymes or cell surface receptors (ABCB1, ABCG2, VEGFA, FCGR2A, NCF4, GSTP1, CRBN) might predict the drug efficacy. Actually, several single nucleotide polymorphisms (SNPs) of ABCB1 exert an effect on substrate affinity of lenalidomide for the transmembrane transporter. Moreover, VEGFA is involved in the anti-angiogenic activity of lenalidomide and might eventually upregulate ABCB1 expression, too. Patients and methods. Genotypes for SNPs were obtained through allele-specific (ASO) probes on germline DNA from peripheral blood. Minor allele frequencies (MAFs) were obtained and the Hardy-Weinberg equilibrium (HWE) was checked. Genotypes were used to infer individual haplotypes by Arlequin and Haploview softwares. Minimal residual disease (MRD) was assessed with ASO primers on either IGH or BCL-1/IGH rearrangements by RQ-PCR in bone marrow samples. TP53 disruption was identified by NGS targeting resequencing and copy number variation analysis. Clinical-biological correlations were screened by automated machine learning methods and validated by both Kaplan-Meier at univariate level and Cox models for multivariate analysis (MV). A logistic regression was implemented to investigate correlations between polymorphisms and MRD kinetics. Results. 278 out of 300 patients (93%) were fully genotyped. The MAF values of the SNPs were very similar to published data and the HWE was confirmed. Most notably, ABCB1 c.2677G〉T/A(W) and VEGFA c.2055A〉C were significantly associated to outcome and are thus described in this abstract. In the case of ABCB1, the three loci were in strong linkage disequilibrium (p
Print ISSN:
0006-4971
Electronic ISSN:
1528-0020
Topics:
Biology
,
Medicine
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